The invention relates to a cock comprising an indexable rotating key.
More specifically, it relates to a cock with a rotating key, the key of which rotates in a tubular housing of a barrel where the key has been axially introduced through one end of the housing up into an axial position determined by blocking means, the sidewall of the housing including passages which open into a housing area through apertures, while the key is designed with passage(s) for blocking these apertures or establishing communication between certain apertures according to the positions of the key during rotation of the key, the cock including in another area of the housing, means (so-called indexing means) for tactilely telling the operator that the key has arrived in a service position where it establishes communication, these indexing means comprising stubs and notches distributed over faces facing the key and the housing so that during a rotation of the key, the stubs penetrate the notches when the key arrives in a service position and they may only emerge therefrom when a substantial force is exerted on the key to rotate it, the key or the barrel being designed so as to allow the stubs to emerge from the notches by an elastic effect resulting from this force.
An example of such a cock is described in U.S. Pat. No. 5,832,959.
In this example, the barrel and the key are both in an elastic material in order to achieve the required elastic effect so that the stubs may emerge from the notches.
Such elasticity is detrimental to the seal of the area into which open the passages of the barrel, all the more so since the indexing means are located in an area of the housing, the internal diameter of which is larger than that of the area into which open passages of the barrel.
US publication 2001/025942 describes a cock, the barrel's housing of which includes a closed base which has a determining raised element between it and the elastic side wall of the housing, an annular groove in which may rotate a ring formed at the end of the key, the stubs and the notches being formed on said raised element and on said ring.